In a mobile communication system, each Base Station (BS) in one cell/sector exchanges data with a plurality of Mobile Stations (MSs) through a radio channel environment. In a system operating in multiple carriers or in a form similar thereto, a BS receives packet traffic from a wired Internet network and transmits the received packet traffic to each MS using a predetermined communication scheme. In this case, determination to which MS at which timing and in which frequency domain the BS transmits downlink (DL) data is DL scheduling. The BS receives and demodulates data transmitted from the MS using the determined communication scheme and transmits the packet traffic to the wired Internet network. Determination to which MS at which timing and in which frequency domain the BS transmits uplink (UL) data is UL scheduling. Generally, an MS having a better channel state is scheduled to transmit and receive data using substantial time and more frequency resources.
FIG. 1 is a diagram explaining a time-frequency resource block.
A resource for communication in a system operating in multiple carriers or in a form similar thereto is broadly divided into a time domain and a frequency domain. This resource may be defined as a resource block which includes N certain subcarriers, and M certain subframes or a determined time unit. Here, N and M may be 1. In FIG. 1, one rectangular denotes one resource block. One resource block includes multiple subcarriers in one axis and a predetermined time unit in another axis. In DL, the BS selects the MS according to a predetermined scheduling rule and allocates one or more resource blocks to the selected MS. The BS transmits data to the selected MS using the allocated resource block. In UL, the BS selects the MS and allocates one or more blocks to the selected MS according to a determined scheduling rule. The MS receives scheduling information indicating that the resource blocks have been allocated from the BS and transmits UL data using the allocated resource.
In a DL scheduling scheme, the BS selects a time-frequency resource block having a better channel state based on a Channel Quality Indicator (CQI) reported from the MS and transmits data using the selected resource block. Since the time-frequency resource block having a better channel state is used, much data can be transmitted while using a limited resource block and total data transmission capacity of the system can be increased. Similarly, in a UL scheduling scheme, a BS scheduler may measure the reception state of a pilot signal (or reference signal) transmitted from the MS to select a time-frequency resource block having a better UL channel state and allocates the selected resource block to the MS. The MS then transmits data in UL using the allocated resource.
Service control information consists of User-Specific Control Information (USCI) and Non-User-Specific Control Information (NUSCI). The NUSCI includes information for the MS to decode the USCI, such as the size of the USCI.
The USCI includes control information for users and includes resource allocation information, power control information, feedback (Hybrid Automatic Repeat reQuest (HARQ) or Acknowledgement/Negative Acknowledgement (ACK/NACK)) information. The feedback (HARQ or ACK/NACK) information about UL data transmission is transmitted through a DL ACK channel and is distinguished from a control block for other USCI.
Group control information may be used to allocate and configure a resource to one or more MSs belonging to one group. The control information may have the format of an A-MAP. For the USCI intended for a group of users, multiple control information elements are individually coded and are masked before transmission to a Cyclic Redundancy Check (CRC) of the A-MAP using an identifier (ID) of the MS (including Station ID (STID) of an individual MS, broadcast STID, and multicast STID). Since the A-MAP is individually encoded and masked to the STID before transmission, the MS performs a blind detection process of an A-MAP transmission region in order to confirm whether an A-MAP is transmitted thereto. In this case, the MS uses an STID, broadcast ID, or multicast ID (e.g. group ID, persistent ID, sleep/idle mode ID, MBS ID, etc.) allocated thereto.
The MS performs blind detection based on a MAP size used in a corresponding system. To reduce the number of times of performing blind detection, the MAP size may be restricted to a prescribed size and a type of the MAP size may be limited. For example, the size of an A-MAP Information Element (IE) may be restricted to three types of 56 (or 64), 96, and 144 or two types of 56 (or 64) and 96. It is assumed that, when one Minimum Logic Resource Unit (MLRU) consists of 48 data subcarriers and two MLRUs consist of 96 data subcarriers, the size of the A-MAP IE is determined as 56 and 96. In this case, the 56-bit A-MAP IE may mapped to one MLRU and a 96-bit A-MAP IE may mapped to two MLRUs, using an encoding method (Tail Biting Convolution Code (TBCC) and puncturing) for a DL control channel.
Generally, a Medium Access Control (MAC) management message for a certain MS may be transmitted to a corresponding MS through a DL burst indicated by an assignment A-MAP of a non-user-specific region. However, since a broadcast message such as a neighbor advertisement (AAI_NBR-ADV) message or a paging advertisement (AAI_PAG-ADV) message is dedicated for multiple non-specific MSs, it is necessary to inform the MS of scheduling information using a method different from a general unicast MAC management message. Accordingly, a definition for a scheduling information transmission method for efficient broadcast messaging is needed.